Robustly integrated electrodes constructed by well‐organized building blocks of active materials are appealing in versatile electrochemical systems. Herein, orderly oriented nanowire arrays (NWAs) of multiple molybdenum‐based compounds (MoXn, MoXn = MoP, MoS2, Mo2C, MoN, and MoO2) on carbon fiber paper (CFP) are generally fabricated by topotactic transformations from molybdenum‐containing precursor NWAs. Extensive structural characterizations reveal that these MoXn nanowires are composed of either closely interconnected nanoparticles or edge‐rich nanosheets. When being used as self‐supported electrodes, these MoXn NWAs/CFP exhibit excellent catalytic activities and stabilities toward hydrogen evolution reaction (HER) in pH‐universal electrolytes. Especially, the best‐performed MoP NWAs/CFP shows comparable or even superior HER performance over platinum benchmark, which holds great promises in HER‐related energy technologies. This work presents a simple yet effective approach toward general synthesis of self‐supported Mo‐based NWAs on CFP, which also possesses huge application prospects in other fields, such as supercapacitors, batteries, and sensors. Nanowire arrays (NWAs) of MoP, MoS2, Mo2C, MoN, and MoO2 are generally synthesized through topotactic transformation from molybdenum‐containing precursor NWAs mounted on carbon fiber paper. Benefiting from the structural advantages, these self‐supported molybdenum‐based NWAs electrodes exhibit excellent electrocatalytic performance toward HER in pH‐universal electrolytes.